Business, science and entertainment applications depend upon computing systems to process and record data. In these applications, large volumes of data are often stored or transferred to nonvolatile storage media, such as magnetic discs, magnetic tape cartridges, optical disk cartridges, floppy diskettes, or floptical diskettes. Typically, magnetic tape is the most economical, convenient, and secure means of storing or archiving data.
Storage technology is continually pushed to increase storage capacity and storage reliability. Improvement in data storage densities in magnetic storage media, for example, has resulted from improved medium materials, improved error correction techniques and decreased areal bit sizes. The data capacity of half-inch magnetic tape, for example, is currently measured in hundreds of gigabytes.
In today's data storage market, customers are required to replace their existing hardware in order to upgrade to the next generation of higher capacity, higher data-rate storage devices and associated media. Using tape-based storage as an example, today there are only two kinds of tape drives currently on the market for a given product family: those for a single older, or legacy, format; and those for a single newer format, e.g., a format less than 2 years old. For customers with libraries containing hundreds and even thousands of drives, this can become an enormous investment of time and resources, sometimes so much so that it may not be financially or practically feasible to upgrade.
Imagine a scenario where the user has a large investment in media of a legacy format. The user wants to upgrade to a new system to decrease archiving time, but is not ready to purchase large quantities of media in a new format, and does not want to invest further in drives in the legacy format. What is needed is a way to allow a user to purchase a single drive that allows the user to use a specific mode of a data storage system (e.g., the legacy format), and when the user is ready, enables functionality that allows the user to use another mode of the data storage system (e.g., the new format).
As another example, consider a company (user) that is ready to upgrade to a new tape format, but is contemplating a merger where the merging company uses a legacy format that is not compatible with the company's present systems, nor with hardware in the new format. If the merger goes through, the company will suddenly need access to the data from the merging company and so will need to purchase drives capable of reading the legacy format. These legacy drives are, of course, purchased in addition to the new format drives. The overall cost, implementation time, and system resources needed may be more than the company is willing to spend. What is needed is a way to allow a user to use a specific mode of a data storage system (e.g., the new format), and if needed allow the user to use another mode of the data storage system (e.g., the legacy format of the merging company).
There is accordingly a clearly-felt need in the art for methods for managing storage systems capable of reading and/or writing in multiple modes, such as reading/writing in different formats. It would also be desirable to provide to customers the ability to read multiple formats for such things as backward and forward compatibility, as well as compatibility across competing formats. These unresolved problems and deficiencies are clearly felt in the art and are solved by this invention in the manner described below.